Three quick thoughts from Monaco's 3-1 Champions League win over Borussia Dortmund at the Stade Louis II on Wednesday.
1. Monaco too good for Dortmund
Germany's Champions League challenge is over, as Borussia Dortmund joined Bayern Munich in exiting at the quarterfinal stage. Dortmund could not overturn a 3-2 deficit from the first leg -- for which the team has justified complaints about being played at all, staged as it was just 24 hours after their team bus had been subject to an attack.
The evidence from Monte Carlo was that the visitors came up against a better attacking team, though those harrowing circumstances should always place an asterisk against this tie.
By four minutes in, Monaco had Dortmund requiring a minimum of three goals to progress. Benjamin Mendy burst from deep, and his shot was only parried by Dortmund keeper Roman Burki into the path of Kylian Mbappe. The 18-year-old needed no further invitation to score a 19th goal in 19 matches.
Dortmund could only try to force themselves back into the match. Skipper Marco Reus blew a 10th-minute golden chance when drilling Erik Durm's cross straight at Monaco goalkeeper Danijel Subasic. Nuri Sahin soon after rattled the post with a dipping left-footed free kick, but Dortmund's hopes were almost certainly extinguished by the 17th minute.
This time, Mbappe played his part in the build-up, linking with Thomas Lemar before the midfielder's deft chip reached an unmarked Radamel Falcao at the far post. The Colombian, one of the best headers of a ball in the game, does not pass up such opportunities. Dortmund still needed three goals, but that would \get them only to extra time.
A first came in the 49th minute after Ousmane Dembele reached the byline after a searing run, and Reus pounced on the layback to blast in. Any possibility of a Dortmund comeback relied on their not conceding again, but Mbappe's pace and strength was a constant menace.
A place in the semifinal thus lay in the balance of which team could get the best from their French teenage prodigy. Nineteen-year-old Dembele was briefly more to the fore as Dortmund began to bang on Monaco's back door, with manager Thomas Tuchel urging his team on and home fans' nerves beginning to jangle. It became an end-to-end affair, with defences stretched to their limits.
But Mbappe was always looking to break on the counter, though it was Falcao who should have killed the tie off in the 65th minute, but he failed to repeat the amazing "dink" he scored at Manchester City in the round of 16, when given plenty of time and space. Mbappe also blew his own chance to book a place in the last four when blazing between Dortmund lines in an inside-right position.
Christian Pulisic was Tuchel's final substitution with 20 minutes to play, but it was Monaco sub Valere Germain, on for Mbappe, who finished the competition when he slotted coolly home after another excellent piece of creativity from Lemar.
2. Mbappe appears almost priceless
In scoring that opening goal, Mbappe became the youngest ever player to score five Champions League goals, taking that record from Real Madrid legend Raul. Even among such glittering Monaco talent like full-back Mendy, 21, midfielder Lemar, 22, playmaker Bernardo Silva, 22, and central midfielder Tiemoue Bakayoko, 22, Mbappe looks something very special indeed, especially in an age when striking talent comes at such a premium.
In a deal that might one day reach £58 million, depending on conditions, Mbappe's predecessor as Monaco prodigy, Anthony Martial, joined Manchester United in 2015 while other strikers like Everton's Romelu Lukaku and Torino's Andrea Belotti are quoted as being worth up to €100 million. Mbappe's talent has shone only briefly so far, but he must already be valued at a similar sum.
Monaco's business model of unearthing talent and then selling at a premium suggests Mbappe and his fellow starlets will soon be on the market. In the meantime, with Falcao alongside him as an experienced foil from whom he can learn plenty, Mbappe's goals are lifting manager Leonardo Jardim's team toward a Ligue 1 title and have returned the Principality's representative to their first semifinal since 2004, when they reached the final at the expense of a Real Madrid team featuring Raul himself.
And should the Spanish giant pull Monaco in Friday's semis draw, they will again have plenty to fear. Mbappe and those young colleagues have been the sensation of this season's Champions League.
3. Tuchel's tactical gambles fall flat
A five-minute delay in kickoff came after Dortmund's coach was slow in arriving at the Stade Louis II, being held outside the squad's hotel for 22 minutes by local police.
That can only have brought echoes of last week's trauma, though Tuchel had sought to turn that harrowing experience into a positive by having Marc Bartra, still recovering from the shrapnel wounds he suffered in the April 11 attack, its perpetrators still at large, give the final speech to the players in the moments before they took the field.
Tuchel had also made a strategic change in consigning Dembele to the bench, kept in reserve alongside Pulisic, but the plight of being quickly 2-0 behind and heading out meant Dembele was introduced in the 25th minute with Durm making way, and looking none too pleased with being hooked.
The return of Reus, absent from the first leg with injury but a scorer at the weekend against Eintracht Frankfurt, could not inspire his teammates.
Talk had been of all-out attack, but that was unfortunately married to a naivety in defence, with there being little to no protection in front of an initial three-man back line. It was through such gaps that Monaco's opener came, and their second, leaving Dortmund, for all their own attacking riches, with far too much to rescue.